Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/09—Carboxylic acids; Metal salts thereof; Anhydrides thereof
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/06—Ethers; Acetals; Ketals; Ortho-esters
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/07—Aldehydes; Ketones
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/15—Heterocyclic compounds having oxygen in the ring

Definitions

• This invention relates to a polycarbonate composition used for medical uses. More specifically, this invention relates to a polycarbonate composition which is less likely to be yellowed when it is subjected to a sterilization treatment with irradiation of gamma rays.
• Polycarbonate is a resin having excellent transparency, sanitariness, dimensional stability and impact strength, which is broadly used in industrial fields, and as instruments and equipment for medical treatment as one field of such industrial fields.
• a sterilization treatment a treatment with ethylene oxide and a treatment with aqueous vapor in an autoclave, for example, have been carried out.
• a treatment with irradiation of gamma rays is generally used because it may be carried out in a dry state, at a low temperature and relatively cheaply.
• polycarbonate has drawback in that it is yellowed by irradiation of gamma rays, and said draw­back is similarly brought about regardless of a medium in which the irradiation is carried out, be it in the air, in vacuo or in the absence of oxygen.
• This yellowing not only degrades the appearance of instruments and equipment for medical use, but also, when, for example, blood is observed through the yellowed instruments or equipment, the blood looks darkish, resulting in giving an unpleas­ant feeling to the patient. Due to this, it is necessary to improve such yellowing to an admissible range.
• an object of this invention is to improve the yellowing of polycarbonate caused by gamma rays with which it is irradiated.
• a polycarbonate composition comprising 100 parts by weight of polycarbonate and 0.1 to 1 part by weight of at least one kind of a compound selected from the group consisting of itaconic acid, itaconic anhydride, benzal­dehyde dimethyl acetal, benzaldehyde propyleneglycol acetal and p-phthalaldehyde.
• Polycarbonate used in this invention is obtain­ed by a reaction of a divalent phenol with a carbonate precursor such as phosgene and diphenyl carbonate.
• divalent phenol there may be cited, for example, hydroquinone, dioxydiphenyl, bis(hydroxy­phenyl)methane, 1,2-bis(hydroxyphenyl)ethane, 2,2-­bis(hydroxyphenyl)propane, 2,2-bis(hydroxyphenyl)butane, 2,2-bis(hydroxyphenyl)hexane, 1,1-bis(hydroxyphenyl) cyclohexane, bis(hydroxyphenyl)ether, bis(hydroxy­phenyl)ketone, bis(hydroxyphenyl)sulfide, bis(hydroxy­phenyl)sulfone, alpha, alpha′-bis(hydroxyphenyl)diiso­propylbenzene and nucleus substitution products of the lower alkyls thereof.
• a part of phosgene may be substi­tuted by terephthalic acid chloride and isophthalic acid chloride.
• Polycarbonate used in this invention may be a homopolymer, a copolymer or a mixture thereof, and may have a branched structure.
• the blending amount is per 100 parts by weight of polycarbonate, 0.1 to 1.0 part by weight, preferably 0.3 to 0.7 part by weight. If the blending amount is less than 0.1 part by weight, the effect aimed at cannot be obtained, and if the blending amount exceeds 1.0 part by weight, the heat resistance at the time of molding becomes inferior, resulting in the poor appearance of the resulting molded article.
• an optional method may be properly adopted.
• a method of mixing the two in a tumbler or a Henschel's mixer and then pelletiz­ing the resulting mixture by an extruder or a method of quantitatively projecting the two into the hopper of an extruder by a feeder and then pelletizing the resulting mixture may be adopted.
• the resulting pellets are molded into medical instruments, medical equipment and the parts thereof by ordinary methods such as injection molding, extrusion molding, compression molding and blow molding.
• composition of this invention may be further blended with a mold releasing agent, a stabilizer, an antioxidant and a coloring agent such as a pigment.
• Medical instruments, medical equipment and the parts thereof produced from the composition of this invention have a small degree of yellowing ( ⁇ Y1) of less than 10 at irradiation of gamma rays of 2.5 megarads (MR) that are sufficient amount of irradiation for steriliza­tion. Accordingly, when blood of a patient is put in, for example, a medical instrument produced from the composition of this invention treated with irradition of gamma rays, the blood does not look darkish, and does not give an unpleasant feeling to the patient as a result.
• ⁇ Y1 small degree of yellowing
• MR megarads
• each of the resulting blends (mixtures) was extruded at 280°C by an extruder to be pelletized.
• the resulting pellets were molded at 340°C by injection molding to obtain a 45 x 50 x 2 mm transparent plate.
• the resulting transparent plate was irradiated with 2.5 megarads (MR) of cobalt 60 gamma rays.
• MR megarads
• the degrees of yellow color Y1 of the transparent plate before and after the irradiation were measured according to JIS K7103, and from the measured values of said degrees, the degree of yellowing ( ⁇ Y1) was sought.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Apparatus For Disinfection Or Sterilisation (AREA)
• Materials For Medical Uses (AREA)

Applications Claiming Priority (4)

Publications (3)

Family

ID=26507913

Family Applications (1)

Country Status (3)

Cited By (3)

Families Citing this family (3)

Family Cites Families (1)

• 1988
  • 1988-10-12 JP JP63254873A patent/JPH0613639B2/ja not_active Expired - Lifetime
• 1989
  • 1989-08-04 DE DE1989620660 patent/DE68920660T2/de not_active Expired - Fee Related
  • 1989-08-04 EP EP19890114481 patent/EP0353776B1/de not_active Expired - Lifetime

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